Catapult



Jan. 7, 19 47. 1.. J. MAXSON ET AL CATAPULT 4' Sheets-Sheet 1 Filed July 21, 1952 L/SLE MAXSON FREDERICK B. @2055 INVENTORS ATTORNEY Jan; 7, 1947. J MAXSQN T 2,413,723

CATAPULT Filed July 21, 1932 4 Sheets-Sheet 2 41 L/SLE a. MAXSON FREDERICK B. afioss INVENTORS a. ATTORNEY Jan. 7, 1947. L. J. MAxso'N ET AL CATAPULT Filed Jul 21, 1952 4 Sheets- Sheet 4 8 6 f 0 w Q I wi 7 v 5 m M m M m 41) A i i PM. 3 UR i F F m i m P 4 .fi/ g C 4 Patented Jan. 7, 1947 UNITED STATES PATENT OFFICE CATAPULT Lisle J. Maxson and Frederick B. .(iross,

United States'Navy Application July 21, 1932, Serial No. 623,808

(Granted under the act of March 3, 1883, as

amended April 30, 1928; 370 0. G. 757) .11. Claims.

Our invention relates broadly to catapults for launching airplanes, and more particularlyto imv proved holddown and release mechanism of the launching car associated therewith.

The principal object of our invention is to provide improved and efficient operating mechfor'securing the airplane to the launching car insure positive release of the same automatically during the launching run.

A further object of our invention is to provide a positive means whereby absolute certainty is assured in the freeing of an airplane from a turned to its starting position, the hold-down mechanism can bereadily set up for receiving another aircraft. I

Another object ofourinvention is to provide .the mechanism of the character described that is rugged, light in weight, andpositive in action.

Reference is .to be had to the accompanyin rawings, forming apart of this specification in which like reference characters indicate corresponding parts throughout the several views and inwhich:

Figure 1 is a detail side elevation of an a r-- plane mounted in starting or battery position upon a launching car of a catapult, incorporating our improved hold-down and releasing mechanism.

Figure 2 is an enlarged fragmentary front view showing portions of the forward hold-down fitting,.and details of .the safety connecting bar.

Figure 3 is a detail side view of parts shown in Figure 2. I

Figure 4 is an enlarged fragmentary front View of the forward hold-down members. c

Figure 5 is an enlarged fragmentary side view ofthe elongated lug extending below the center of the pontoon.

Figure '6 is an enlarged detail side view of one of the rear hold-down hooks.

Figure 7 is a side view of the rear hold down hook and its application to the side of the launching car. Y

Figure 8 is .a bottom viewof the hand wheel and its locking member.

Referring more particularly to the drawings 28in'dicates a portion of a conventional catapult beam withta mechanismfor the acceleration of launchingv car upon which'is attached a typical airplane 22 being shown more or less diagrammatically. For the purpose of illustration our improved mechanism has been shown as applied. to an airplane of theseaplane typeequipped with a single pontoon 23 having a V bottom 23' and single-step construction 23 The launching car 2i isfp'ropelledtalong the guide rails-of the catapultifll by means of power applied to the launching cable 24. The cable 2:? being connecte'ditothe car 2|, as..at 25 and is run forward overthe sheave '26 and then to a catapult venginev (not shown) The car .2l is constructed of metal fabricated structure composed ofrnumerous castings, plates and angles, secured together to'form a rigid unit.

The customarylshoes'fl are located at the four corners of the earl! forfsli'ding engagement along thersidera-ils 2B of the catapult beam 2 3.

In the voperation 0f the..device' it is also the practice toprovide a release mechanism or breaking bar betweenthefcar and theflaunching beam that williseparate only after suflicient predetermined amount .of power has been'developed to accomplish a perfect launching, but since this featurevdoes notconstitute novelty in the present invention'further descriptioniis omitted.

A saddle .29 secured to the structural members of the car v2| provides a rest for the rear end of the pontoon 23 and a support. forthe rear'h0lddown hooks 30 for connecting the .pontoon'zt'to the launching car "2|, while'the forward end, of

the car is provided with latch members 3| which are V-equipped with removable securing pins in the apertures '32 and pivot about the bolts inserted at. 33. The inner ends of the latch members 31 are machined off so as to form bearing faces 34, for engagement with the shoulder '35 of the central forwardifitting 36 of the pontoon 23. The rear end of the fitting 35 extends below the lines of the "carstructure as at 37 and acts as the propulsion contact betweenthe car and the pontoon, whilethe forward endof the fitting 3.6 formsan abutment for the coupling mechanism (to be described later) After'the .ca1r2l :has been brought back to battery position at'thelrear end of the catapult beam 28 the airplanei22=islowered by a hoisting crane and sling (not showm -to the battery position,the float 23is secured'to the car 2! by means of the combined hold-down and automatically releasable hooks 30 which are securedto the'sides of the saddlestructure' 29 by meansof bolts or the like 38 passing through the apertures in the flange plate 33 of the brackets 46. The hooks 33 are mounted by a passing bolt 41 through apertures in the side plates 42 of the brackets 46, and through an elongated slot 43 formed in the shank of the hook. A hand operated Wheel 44 is threaded to the lower end of'the hook 39 so that when the same is raised to full line psition of Figure 7 the lip 45 will pass over the flange 45 of the plates 46 secured to the side of the pontoon 23. The wheel 44 is then turned up on the threads until the bevelled faces 41 are brought up against the edges of the elongated aperture 48 formed in the bracket 40. In order to insure the parts against accidental release a dog 56 is hinged at to the bracket 46 and engages notches 52 formed in .the flange of the wheel 44. The plates 46 have the upper face of their flanges 46 slightly inclined in a forward direction as Shown more clearly in Figure 6 so that as the airplane is launched forward the hook 36 will slip o-fi at the back end more readily.

In addition to the hold-down mechanism 36 located at the rear of the step 23" of the pontoon 23, and the forward hold-down members 3! in engagement with the fitting 36 secured to the bottom 23' of the pontoon 23, we provide a further safety coupling bar 53 to prevent accidental separation or displacement of the pontoon 23 from the launching car 2| while in starting or battery position upon the launching beam 26. The coupling bar 53 is pivotally connected by a removable pin 54 located at the lower end to an adjustable fitting 55'mounted on a bracket 56 which is set at the desired position by means of f the threaded collar 51 and lock nut 58. The bracket 56 is secured by bolts 59 to the beam 26. The bar 53 has a lip 60 which is placed in contact at the foremost point of the fitting 36 of the pontoon bottom 23' and is held in this po' launching run has begun and rest upon the resilient pad 63 until reset for another launching.

To reset the bar 53, the pin 54 is removed and the nose is Slipped through the slot in'beam 23 between the reinforcing angles 64 and through the link fitting 6| and placed in contact with the fitting 36 of the pontoon.

The operation of our improved device is as follows;

Before the aircraft is placed on the launching car, the books 3!] are lowered out of position, the latch members 3| are opened as shown by the dotted lines in Fig. 4 and the bar 53 is removed from its fitting by taking out pin 54. The

airplane is then lowered until the float rests on the launching car, where it is made secure against upward and sidewise displacement by placing hooks 36 in contact with flanges 46' and securing the latches 3| by pin 32 so that bearing faces 34 rest against the shoulders 35 of the fitting or launching caris released or starts to move forward, the lip 66 of bar 53 is pushed out of contact with the lug 36 and the forward movement of the car causes the bar to rotate about its pivot point, the pin 54, until it is entirely displaced from the slotted fitting BI and permitted to drop to the pad 63. Thus, by a short or very limited movement of the launching car, the means for preventing creeping of the airplane in battery position is displaced and the airplane is free to move out forward from the launching car as soon as the acceleration of the airplane exceeds that of the car.

It will be understood that the above description and accompanying drawings comprehend only the general and preferred embodiment of our invention, and that various changes in construction, proportion and arrangement of parts may be within the scope of the appended claims, and without sacrificing any of the advantages of our invention.

The herein described invention may be manufactured and used by or for the Government of the United States for governmental purposes without the payment to us of any royalties thereon.

What we claim is: I

1. In a hold-down connection for securing airplanes to catapulting apparatus, in combination, a landing gear, a launching car, flanged fittings secured to said car, brackets supported by said car, hooks pivotally connected to said brackets adapted to engage flanged fittings, and threaded hand wheels for tensioning said hooks, and means for locking said wheels in adjusted position supported by said brackets.

2. In anairplane launching apparatus, in combination, a launching beam, a launching car adapted to travel on said launching beam, an airplane having a float supported by said car, a lug projecting downwardly from the bottom of said float, a cross beam attached to said car for contact with said lug to impart a propelling motion to said airplane by forward movement of said car, flanges extending from said lug, latches secured to said car transversely of said lug and having bearing faces for engagement with said flanges, securing pins removably inserted through apertures in said latches for pivotally moving said latches when seating the airplane on said car, a plurality of flanged plates'projecting horizontally from the sides of the float of said airplane, a plurality of adjustable hooks adapted to be moved transversely to engage said flanged plates upon loweringof said airplane on said car, thereby restricting the-airplane when leaving th car to horizontal movement. 7

3. In a coupling mechanism for holding the rear of an airplane down upon a launching car, in combination, flanged brackets projecting outwardly from the side of the airplane, and adjustable hooks pivotally mounted upon the launching car and adapted to engage said flanges to prevent the airplane from lifting vertically.

4. In a coupling mechanism for restricting the rear end of an airplane to horizontal movement while mounted upon a launching car, in combination, a plurality of flanged plates projecting horizontally from the sides of the airplane, a plurality of adjustable hooks adapted to be moved transversely to engage said flanged plates upon seating the airplane on the car to restrictthe airplane to horizontal movement when being freed from the car.

5. In a coupling mechanism for holding the forward end of an airplane down upon a launching car, in combination, a lug secured to the airplane and having horizontally located flanges extending from the sides thereof, a plurality of latch members pivotally mounted to the launching car and adapted to engage the horizontal flanges of said lug for holding down the airplane, and removable securing pins adapted to hold said latch members in place after the airplane is lowered onto the launching car.

6. A launching apparatus for an aircraft, in combination, landing gear having a lug secured to and projecting below the bottom thereof, a launching beam, a launching car mounted on the beam, latching means on the car for engaging the lug of said landing gear so as to hold the forward portion of said car against upward displacement, flange fittings on the side of the gear pivot means adjustably secure to the car for engaging the fittings to hold the rear portion of the gear in position, and means pivotally secured to the launching beam to bear against said lug to prevent forward movement of the gear when the airplane is in battery position, and to automatically move out of position when the launching car is moved.

7. A launching apparatus for an aircraft, in combination, landing gear having a lug secured to and projecting below the bottom thereof, a launching beam, a launching car adapted to reciprocal motion on said beam, latching means on said car for engaging said lug, and means for holding the gear against forward motion when the launching car is in battery position, said holding means comprising a lever pivotally secured to the beam and a guide member secured to the car for holding the lever against the lug, the lever being automatically displaced from the lug as soon as the car moves forward.

8. A launching apparatus for an aircraft, in combination, a landing fioat having a lug projecting from the bottom thereof, a launching beam,

a launching car having a cross bar member with latching means for engaging said lug when the gear is lowered into battery position, a lever p-ivotally secured to the launching beam, and a guide link attached to said cross bar member for holding the lever against the lug while the launching car with the aircraft is in battery position, the

6 lever being automatically displaced from the log? and guide link as soon as the car moves forward.

9. A launching apparatus for aircraft comprising a launching beam, a launching car adapted to reciprocal motion on said beam, means on said car for holding the forward portion of an aircraft against upward and sidewise displacements, means for retaining the rear portion of the aircraft against upward and sidewise displacements, and a hold-back mechanism supported on said beam for preventing the creeping of an aircraft while in battery position on the launching car.

10. A launching apparatus for aircraft comprising a launching beam, a launching car on said beam, U-shaped members carried by said launching car, said U-shaped members providing guiding and sliding means for said launching car on said beam, and hold-back mechanism supported on said beam for preventing the creeping of an aircraft while in battery position on the launching car and automatically releasable from said aircraft by the initial forward motion of said car from starting position.

11. A launching apparatus for aircraft comprising a launching beam, a launching car adapted to reciprocal motion on said beam, U-shaped members carried by said launching car, said U- shaped members providing guiding and sliding means for said launching car on said beam, means for holding the forward portion of an aircraft against upward and sidewise displacements, means for retaining the rear portion of the aircraft against upward and sidewise displacements, and a hold-back mechanism supported on said beam for preventing the creeping of an aircraft while in battery position on the launching car and automatically releasable from said aircraft by the initial forward motion of said car from starting position.

LISLE J. MAXSON. FREDERICK B. GROSS. 

